package sicket;

import java.io.*;
import java.net.ServerSocket;
import java.net.Socket;
import java.nio.charset.StandardCharsets;
import java.util.ArrayList;
import java.util.List;
import java.util.Scanner;

/**
 * 聊天室服务端
 */
public class Serve {
    private ServerSocket serverSocket;
    //该集合存放所有客户端输出流用于广播消息
    private List<PrintWriter> allOut=new ArrayList<>();
    public Serve(){
        try {
            System.out.println("正在启用服务端...");
            serverSocket=new ServerSocket(8088);
            System.out.println("服务端启动完毕!!");
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    public void start(){
        try {
            while (true) {
                System.out.println("等待客户端连接");
                Socket socket = serverSocket.accept();
                System.out.println("一个客户端连接了");
                //启动一个线程处理与客户端的交互
                ClientHandler handler=new ClientHandler(socket);
                Thread t=new Thread(handler);
                t.start();
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    public static void main(String[] args) {
        Serve serve=new Serve();
        serve.start();
    }
    public class ClientHandler implements Runnable{
        private Socket socket;
        private String host;//记录该客户端的IP地址
        public ClientHandler(Socket socket) {
            this.socket=socket;
            host = socket.getInetAddress().getHostAddress();
        }

        public void run(){
            PrintWriter pw=null;
            try {
                InputStream ins = socket.getInputStream();
                InputStreamReader isr = new InputStreamReader(ins, StandardCharsets.UTF_8);
                BufferedReader br = new BufferedReader(isr);

                OutputStream out=socket.getOutputStream();
                OutputStreamWriter osw=new OutputStreamWriter(out,StandardCharsets.UTF_8);
                BufferedWriter bw=new BufferedWriter(osw);
                 pw=new PrintWriter(bw,true);
                //将该输出流存入共享集合allOut
                synchronized (allOut){
                    allOut.add(pw);
                }
                System.out.println(host+"上线了,当前在线人数"+allOut.size());

                String line;
                while ((line = br.readLine()) != null) {
                    System.out.println(host+"说:" + line);
                    //将消息回复给所有客户端
                    synchronized (allOut){
                        for (PrintWriter o:allOut){
                        o.println(host+"说"+line);
                        }
                    }
                }
            } catch (IOException e) {
                e.printStackTrace();
            }finally {
                //处理客户端断开后的操作
                synchronized (allOut){
                    allOut.remove(pw);//将当期按客户端输出流从共享集合中删除
                }
                System.out.println(host+"下线了,当前在线人数:"+allOut.size());
                try {
                    socket.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
    }
}
